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Finding the Fourth Proportional to 320.14, 439.24 and 312.11

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Solution

The fourth proportional to 320.14, 439.24 and 312.11 is: 428.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.14 : 439.24 = 312.11 : x
  2. Step 2: Convert to fraction form
    320.14/439.24 = 312.11/x
  3. Step 3: Cross multiply
    320.14x = 439.24 × 312.11
  4. Step 4: Simplify right side
    320.14x = 137,091.20
  5. Step 5: Solve for x
    x = 137,091.20/320.14
  6. Step 6: Final answer
    x = 428.22

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.